Surgical robot and robotic controller

ABSTRACT

The present invention was developed by a neurosurgeon and seeks to mimic the results of primate neurological research which is indicative of a human&#39;s actual neurological control structures and logic. Specifically, the motor proprioceptive and tactile neurophysiology functioning of the surgeon&#39;s hands and internal hand control system from the muscular level through the intrafusal fiber system of the neural network is considered in creating the robot and method of operation of the present invention. Therefore, the surgery is not slowed down as in the art, because the surgeon is in conscious and subconscious natural agreement and harmonization with the robotically actuated surgical instruments based on neurological mimicking of the surgeon&#39;s behavior with the functioning of the robot. Therefore, the robot can enhance the surgeon&#39;s humanly limited senses while not introducing disruptive variables to the surgeon&#39;s naturally occurring operation of his neurophysiology. This is therefore also a new field, neurophysiological symbiotic robotics.

[0001] The present application is a continuation in part of U.S. patentapplication Ser. No. 10/321,171, filed on Dec. 17, 2002, the contents ofwhich are hereby expressly incorporated by reference thereto into thepresent application.

BACKGROUND

[0002] The present invention relates to the field of robotic andcomputer assisted surgery, and more specifically to equipments andmethods for robotic and computer assisted microsurgery.

[0003] As shown in U.S. Pat. No. 5,943,914 to Morimoto et al.,“Master/slave” robots are known in which a surgeon's hand input isconverted to a robotic movement. This is particularly useful for motionscaling wherein a larger motion in millimeters or centimeters by thesurgeon's input is scaled into a smaller micron movement. Motion scalinghas also been applied in cardiac endoscopy, and neurosurgical targetacquisition brain biopsy (with a needle) but only in one degree offreedom, for example only for insertion, not for a full range of naturalhand movement directions, .e., not for all possible degrees of naturalmotion, Cartesian, spherical or polar coordinate systems or othercoordinate systems.

[0004] Further, in the prior art, surgical robots have been purposefullydesigned to eliminate the natural hand tremor motions of a surgeon'shand which is about a 50 micron tremor which oscillates with someregularity. The common presumption is that tremor motion createsinaccuracies in surgery. Therefore, robots have been tested whichentirely eliminate the surgeon's natural hand tremor. See “A Steady-HandRobotic System for Microsurgical Augmentation” Taylor et al.,International Journal Of Robotics Research, 18(12):1201-1210 December199, and also see “Robotic-assisted Microsurgery: A Feasibility Study inthe Rat” LeRoux et al., Neurosurgery, March 2001, Volume 48, Number 3,page 584

[0005] The way the primate body handles proprioceptive perception is viasensory feedback scaling (up and down) at the muscular level through theintrafusal fiber system of the Gamma efferent neural circuit. Thissystem responds dynamically to changes in the anticipated muscleperformance requirement at any instance by adjusting muscle tone withincreased discharging for arousal and attention focusing states, anddecrease output for resting and low attention states. The muscle spindleapparatus that does this is located in the muscle body, thereforefeedback sensory scaling for muscle positioning, force, length andacceleration is partly programmed at the effector level in “hardware” ofthe body, i.e., the muscle itself. The evidence indicates a 10 cycle persecond refresh rate for the human neurophysiological system in general.

[0006] Joint position and fine motor function of the fingers occursthrough unidirectional (50% of fibers) and bi-directional (50% offibers) sensing at the joint structure. This coding is for rotationabout an axis, but not for force and no clear speed of rotationfeedback.

[0007] Cutaneous receptors in the skin code for motion, by modulatinghigher centers in the thalamus and cerebral cortex. This can be timed toabout 75 ms delays before motion occurs, three neuronal synaptictransmission delays. These sensors are primarily distal to the joint ofrotation and distal in the moving effector limb. Finally, the sense ofcontact is totally discrete from the above motion feedback sensorysystems and the neural pathways and integration centers in the deephemispheres and cerebral cortices function independent of motion to alarge degree.

[0008] Force reflectance sensing is also known in order to providetactile or haptic feedback to a surgeon via an interface. See“Connecting Haptic Interface with a Robot” Bardofer et al., Melecon200—10^(th) Mediterranean Electrotechnical Conference, May 29-31 2000,Cyprus.

[0009] However, in testing, all of these techniques ultimately slow downthe actual surgery especially when performed in conjunction with amicroscope for viewing the operation. The procedure time is typicallyincreased by two to three times. See Robotic-assisted Microsurgery: AFeasibility Study in the Rat” cited above. It is believed that thisaffect is related to dissonance between a surgeons expectations and thefeedback and motions of a surgical robot in use.

[0010] Another major design issue regards the choice between locatingthe surgeon in his normal operating position adjacent to the surgicalfield or locating the surgeon more remotely from the normal operatingposition at a terminal with a joystick and viewing screen for example.The prior art elects to locate the surgeon remotely from the traditionaloperational position about the head and to use monitors to display theoperation to the surgeon.

SUMMARY OF THE INVENTION

[0011] The present invention was developed by a neurosurgeon and seeksto utilize the results of primate neurological research which isindicative of a human's actual neurological control structures andlogic. Specifically, the proprioceptive and tactile neurophysiologyfunctioning of the surgeon's hands and internal hand control system fromthe muscular level through the intrafusal fiber system of the neuralnetwork is considered in creating the robot and method of operation ofthe present invention. Therefore, the surgery is not slowed down as inthe prior art devices, because the surgeon is in better conscious andsubconscious natural agreement and more accurate harmonization with therobotically actuated surgical instruments based on neurologicalmimicking of the surgeon's behavior through the functioning of therobot. Therefore, the robot can enhance the surgeon's humanly limitedsenses while not introducing disruptive variables to the surgeon'snaturally occurring operation of his neurophysiology. This is thereforealso a new field, neurophysiological symbiotic robotics.

[0012] One result of the present invention, and associated discoveries,was that preservation of the hand tremor motion was unexpectedly foundto help to maintain a natural and efficient synergy between the humansurgeon and the robotics, and thus not disrupt the normal pace ofsurgery. This is believed to be because the present invention recognizesthat the surgeon's own neurophysiology beneficially uses tremor motion,and moreover the neurophysicology of the surgeon expects and anticipatesthe tremor to exist for calibration purposes. For example, at themuscular level, tremor is used neurologically for automated feedbacksensory scaling and also as part of probing, positioning, and trainingprocess of the muscle spindle and muscle. Therefore, human muscleactually performs some calibration and “thinking” itself includinganticipating forces to come based on historically learned data orinstinct. Thus, preservation of hand tremor may be counter-intuitive,and the opposite of what is taught and suggested in the art.

[0013] Additionally, the present invention locates the operatorinterface of the controller robot to work in basically the sameorientation and location as in a standard manual operation. Inneurosurgery for example, the controller robot may be included in a halostructure fixed to the patient's head in much the same way as a standardretractor system is affixed. Alternatively, the controller robot may belocated on a stand, the body, the surgical table or on a rolling orportable platform. In this manner, the surgeon is not immediately forcedto operate in an unnatural, detached and isolated environment which isforeign to traditional procedures to which his own body and neurologicalresponses are accustomed.

[0014] Therefore, in summary, the present invention in its variouscontroller robot embodiments may include the following features whichmay be adjustable by the surgeon to his or her individual requirements:

[0015] Hand tremor sensing, management, modulation and smoothing withscaling capability;

[0016] Motion sensing and scaling;

[0017] Force sensing and scaling including squeeze force scaling, andforce reflectance feedback scaling;

[0018] Contact sensing and indicating;

[0019] Contact reflectance sensing, i.e., reflectance force sensing onthe tip of an instrument;

[0020] Endoscopic “tip vision” sensors located to look down the tip ofthe surgical instrument;

[0021] External source interface capabilities, including but not limitedto, magnetic resonance imaging, computer aided tomograph, and continuousframeless navigation;

[0022] Microscope interface capabilities; and

[0023] Instrument selection interface capabilities to allow automatedpicking of surgical instruments.

[0024] The present invention may be embodied in a controller robot forperforming surgical procedures. The controller robot may have a roboticsportion. The robotics portion may have at least one surgical instrument.The controller robot may also have an interface portion having a displayand an input device. The controller robot may also have a controllerportion having hardware and software for transforming input provided bya surgeon operator via the interface portion into motion of the surgicalinstrument of the robotics portion. The robotics portion may also haveforce detection sensors for determining force reflectance from tissue incontact with the surgical instrument.

[0025] Alternately, the present invention may be embodied in a method ofcontrolling a surgical instrument connected to a surgical robot whereinthe first step may be locating a controller robot between a handle and asurgical instrument. Next, incident tremor force components (TF) presenton the handle generated by the surgeon's hand may be sensed. Then, anincident motion force (MF) component present on the handle generated bythe surgeon's hand natural motion (NM) as the surgeon moves the handlemay be sensed. Then, the incident tremor force (MTF) components in thecontroller robot may be modulated and scaled. Then incident motion force(MMF) components in the controller robot may also be modulated andscaled. Then, a modulated and scaled output movement (MSOM) includingthe modulated and scaled incident motion force (MMF) and the modulatedand scaled incident tremor force (MTF) in the controller robot formoving the surgical instrument via the controller robot, in all degreesof instrument freedom, in response to the natural movement (NM) inputtedby the surgeon on the handle, may be created. A modulated and scaledmovement (MSOM) to move the surgical instrument with all anatomicallypossible degrees of human hand motion freedom, in response to arespective natural movement (NM) inputted by the surgeon on the handlemay then be outputted to the surgical instrument. Incident reflectanceforce (RF) components from the surgical instrument in the controllerrobot when the surgical instrument is near body tissue may then besensed. The reflectance force (RFMS) components in the controller robotmay be modulated and scaled. The modulated and scaled reflectance force(RFMS) may then be imposed on the handle. Furthermore, acontact/non-contact condition may be sensed at the surgical instrument,and provided to the surgeon via a display to the surgeon.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026]FIG. 1 is a side view of a patient on an operating table with acontroller robot engaged to a patient.

[0027]FIG. 1a is a top view of the controller robot engaged to apatient.

[0028]FIG. 1b is a top view of the controller robot engaged to apatient.

[0029]FIG. 2 is top view of a second embodiment of the controller robotin which the controller robot is affixed to a stand.

[0030]FIG. 3 is a representation of a controller robot in operation withassociated data displays to.

[0031]FIG. 4 shows a conceptual representation of an instrumented test.

[0032]FIG. 5 shows a prior art mount for surgery from U.S. Pat. No.6,463,319.

[0033]FIG. 6 shows an embodiment of the present invention wherein thecontroller robot is embodied in controller, robotics, interface, andmobile base portions.

[0034]FIG. 7 shows an embodiment of an augmented microsurgicalinterface.

[0035]FIG. 8 shows a controller robot in an operating room environment.

[0036]FIG. 9 shows an interface between a robotic arm for a controllerrobot with a surgical instrument unit.

[0037]FIG. 10 shows a robotics portion according to present inventionover which a sheath has been draped to provide a sterile barrier betweenthe robotics portion and a patient.

[0038]FIG. 11 shows a notional instrument unit as may be used in acontroller robot.

[0039]FIG. 12 shows a notional instrument unit as may be used in acontroller robot, incorporating distance sensing equipment to providedistance feedback to a surgeon operator.

[0040]FIG. 13 shows a notional instrument unit as may be used in acontroller robot, incorporating dual light pointers to allow thedistance between illuminated points to provide distance cueing to asurgeon operator.

[0041]FIG. 14 shows distance differences based on instrument distancefor an instrument unit such as that shown in FIG. 13.

[0042]FIG. 15 shows a notional single instrument unit embodying aninterface compatible with the interface as shown in FIG. 9.

[0043]FIG. 16 shows a notional augmented microsurgical interface(hereafter “AMI”) for a controller robot.

[0044]FIG. 17 shows a notional rotary magazine for instruments for acontroller robot.

[0045]FIG. 18 shows a notional input device for a controller robot.

DETAILED DESCRIPTION OF THE INVENTION

[0046]FIG. 4 shows conceptually how the present invention creates avirtual surgical instrument by placing controller robot 10 between thesurgical instrument 30 and the handle 32 of the instrument. In this way,the surgeon is not isolated or made remote from the operation, butinstead remains in an environment to which he is accustomed. Althoughthe conceptual drawing illustrates a structural connection between theinstrument or instrument and the handle, the controller robot may beindirectly linked between the instrument and the handle.

[0047] Extrapolating new surgical concepts from known primate researchhave been critical to method of the present invention, as describedgenerally below.

[0048] Therefore, as shown in FIGS. 1-3, in the controller robot 10 ofthe present invention, the creation of the perception of “contact” perse in a surgical robot controller robot 10 should not be based onacceleration/motion reflectance, but rather should be based purely on abinary sense of touch (see “contact indicator” display in FIG. 3) inorder to move properly be consistent with the human neurological system;which is different from motion sense.

[0049] In a human, the motion sense takes over after contact informationhas been initiated with a fairly fixed delay measured in milliseconds.In the present invention, limitation of contact information may betransferred through the controller robot 10 to the handle 32 to thesurgeon's hand through a physical feedback such as a jerk or vibration,or optically or audibly through a display verifying the contact with thetarget or proximate tissue in the surgical field.

[0050] True force reflectance perception has to have high refresh ratesmeasured in milliseconds. This is consistent with numbers described inthe prior art literature which give tactile bandwidths on the order of500-1000 Hz. For instrument contact with soft surfaces, 100-200 Hz maybe more than adequate.

[0051] Muscle sensing seeks information regarding amplitude and timewith suitable rise and fall curves to allow to synthesize the discretemotor performance function in question virtually in the controllerrobot.

[0052] Also, the fact that the entire human sensory/motorneurophysiologic system works in an “anticipatory mode” with modulationby internal experience and external sensory data indicated above may beutilized in the control function between the operation and theinstrument. The human anticipatory mode defines the need for suitableanticipatory delays between contact, muscle loading and neuraltransmissions times. All of these parameters may be scrutinizedsubconsciously by the operator via optical feedback (microscope directvision or endoscopic instrument tip tracking) during the surgery.

[0053] In light of the above, a first embodiment for a controller robot10 is discussed below. FIGS. 1a and 1 b show the parts of a controllerrobot 10 located about a head during surgery. A pinned head holder 12may be attached via cranial screws 16 to a patient P. The pinned headholder 12 may provide a base for mounting a right robotic arm 14 and aleft robotic arm 24 via robotic arm mounts 18. Robotic arm mounts 18 areshown as motorized and may provide for controlled motion includingmotion on the micron scale or smaller, and may be moveable andstabilized in radial tracks 20. The robotic arms may include sub-armssuch as those shown in 14 a, 14 b, 24 a, and 24 b. Alternatively, therobot arm may be mounted on a portable tray system which would be fixedto the table which is turn fixed to the patient or other combination forfixation. Surgical instruments may be located at the end of the roboticarms as shown and may be interchangeable. An automated instrumentchanger such as a carousel is contemplated as well. Handles 32 may mimicactual handles from manual surgical instruments. i.e., they may be thesame size and shape, and can be squeezeable or fixed, in order toprovide realism to the surgeon.

[0054]FIG. 3 shows a number of the data displays which are envisioned aspart of controller robot 10.

[0055] Typically, a microscope display 40 is used to view aneurosurgical surgical field, such as, for example, a procedure wheresurgical movements of the surgical instrument tips can be on the orderof 100 micrometers. When viewing the visual operation through themicroscope the surgeon may be viewing a magnified image so that visualmotions of an instrument are magnified. Therefore, motion scalingwherein a controller robot scales down the surgeon's movement of forexample to 1 cm to 100 micrometers may be useful.

[0056] Therefore, a settings display 50, which may include a motionscaling feature, may be included as part of controller robot 10. Thedisplay 50 may include hardware which runs software to control themotorized robotic arms. The display 50 may include a touch screen orother interface, however the software, and hardware may be of anysuitable design and this invention is not limited to any particularhardware, software or robotics per se. The present invention prefers touse robust hardware and software platforms for control electronics asrequired for space based applications where failure prevention isparamount. Applicable ISO and/or IEEE standards may provide furtherinformation regarding applicable format tolerances. Each surgeon whouses the robot controller 10 may store his or her personal settings sothat his or her personal settings can be restored at a later time, andthus the machine may not have to be retrained.

[0057] Returning to FIG. 3, other adjustable settings are shown. Anunexpected result of the present invention in concept is thesignificance of tremor regulation and management including both scalingand smoothing of the tremor oscillation. Hand tremor is a spuriousmotions which may be present in surgery. Neurological tremor is usuallya 50 micrometer (or micron) range excursion and is an oscillation withsome regularity that increases with stress. A trained neurosurgeon'shand tremor is usually in the range of 50 to 100 microns, i.e., under amillimeter. The present concept implements the results of primateresearch which suggests that hand tremor is not an unwanted artifact ofevolution, but rather a useful and necessary product of human evolutionused for natural calibration. Typically, a hand tremor frequency can beat about 8 cycles per second and this regularity may be used by thesurgeon's nervous system to calibrate his movements. The human nervoussystem uses tremor to calibrate its movements almost automatically orsubconsciously, and particularly in conjunction with coordination withoptical recognition, i.e., hand/eye coordination, such as when a surgeonmoves his hands his eyes register and acknowledge the tremor which isused to calibrate his movements neurologically. This neurological factis ignored by systems which seek to entirely filter and eliminateneurological tremor. This neurological operation may be utilized by thepresent invention to provide consistent feedback to a surgeon utilizingthe controlled robot. Thus, such utilization may create tremor motion atthe tip of the surgical instrument, such that a surgeon looking througha microscope at the tip of his hand held instrument will see tremormotion and his own neurological system within his body will use tremorto neurologically and automatically calibrate his eye motions with hishand motion. Therefore, such tremor management may be important tosurgeons and other human mimicking robotics.

[0058] In practice, due to magnification under a microscope duringmicrosurgical procedures, the surgeon's own optical system is not in 1:1natural correspondence with the optical image. Therefore, “tremorscaling,” i.e., modification and adjustment of the force of the tremoroutputted to the surgical instrument to be harmonized at a natural levelwith the optical magnification selected, may be a very important conceptof the present invention which can be provided via the controller robot10. Such tremor scaling may help avoid impeding the pace of theoperation. The tremor scaling feature is preferably also implemented inconjunction and harmony with motion scaling. For example, reducingnatural tremor to half speed may improve the surgeon's movement. This isbecause the controller robot 10 in toto has enhanced the surgeon'smovements.

[0059] For example, a typical surgeon's real hand motion or excursion of5 centimeters with the surgical instrument may contain a 50 microntremor excursion oscillation, and the motion at the surgical instrumenttip (at the actual surgical site) may be scaled down by the controllerrobot 10 to become a 5 millimeter motion (motion scaling) but may alsoincludes a scaled down tremor motion of 2 microns (or any value thesurgeon is personally comfortable with given settings based on trial anderror wherein such settings may be stored in the controller robot 10from one surgery to the next). Thus, the controller robot mayeffectively maintain in a relative fashion, the effect of the surgeon'shand excursion even under magnification under a surgical microscope,through scaling. Therefore, when a surgeon looks at the surgicalinstrument through a microscope, what he of she may see is a roboticallycontrolled but natural looking 2 micron tremor excursion (minified from50 microns) over his 5 millimeter motion (minified from 5 centimeters).This may enhance the surgeon's actual useable natural range and allowhim to have enhanced capabilities by first allowing him make his handmotions on a human scale of 5 centimeters and then scaling his motiondown to 5 millimeters. Therefore, he or she may move his or her handaccurately in the micron range. Such scaling may be performed by thecontroller robot 10 in all degrees of freedom associated with a surgicalinstrument in use, or only with regard to selected degrees of freedom.Second, by incorporating and scaling a tremor motion, the naturalcalibration of the surgeon's neurological system may be maintained whenthe surgeon looks through the microscope.

[0060] Additionally, given that calibration based on tremor is animportant feature for proper motion of the surgeon's hand, the ? mayassist a surgeon by eliminating or processing anomalies from the tremoroscillation to allow the surgeon's neurological system to betterself-calibrate itself, referred to hereafter as “tremor smoothing” or“tremor shaping.” Therefore, if a surgeon is looking at the tip of aninstrument, his or her optical feedback which is used for controllinghis or her hand can be influenced if anomalies and great irregulardeviations in his tremor signal are smoothed to be an oscillation withcyclical regularity. Thus, “tremor smoothing” can actually assist thenatural neurological calibration, rather than slowing it down byeliminating tremor as taught in the prior art.

[0061] It is envisioned that in the present invention the controllerrobot 10 when first used may have to be trained, i.e., optimal settingsdetermined on animal tissue, in order for the surgeon's initial settingsto be derived. Thereafter, the surgeon, while actually using thecontroller robot 10 on humans, may also store his or her settings whichcan be analyzed in real time. A surgeon can store multiple modes, andmay “shift gears” during a procedure depending on stored settings.Therefore, enabling personalized surgical robotic symbiosis is anothernew feature of the present invention, such symbiosis may be enhanced byproviding the controller with an ability to predictively apply storedsettings which gives the controller robot a layer of artificialintelligence which is designed to mimic the artificial intelligence ornatural responses naturally present in the neurological system and forexample in the muscle tissue.

[0062] Force scaling may be incorporated in the robotic controller inall degrees of motion. For example, a neurosurgeon may be capable ofapplying 0.01 Newtons of force as his or her minimum force. However,delicate tissue may require a smaller force to be applied to avoiddamaging the tissue. Therefore, force scaling may allow a surgeon toscale or minify the actual force presented to the surgical instrument30. This may be accomplished though the controller robot 10. Conversely,feedback forces may be scaled up or magnified. Significantly, this mayenhance the surgeon's natural perception of the tissue's resistance,density, and elasticity.

[0063] The present invention may enable force scaling in all instrumentdegrees of freedom, i.e., the scaling is not limited to one direction asin some prior art cardiac endoscopy robots for example. Therefore, alldegrees of freedom of movement may be enabled. For example, thecontroller robot may move a surgical instrument in seven degrees offreedom, and such forces and displacement magnitudes may be sealed ormodulated in each of the seven degrees of freedom.

[0064] Force feedback or force reflectance may enable the tip of thesurgical instrument to relay through the controller robot 10 thefeedback forces to the handle 32. Feedback on the handle 32 may bethought of as a virtual reality representation of the microsurgeryenvironment and the tip. Such force feedback may also be capable ofbeing scaled in a continuous real time fashion. Continuous resistance,elasticity, kickback movements, jerks or other movements may bepresented at the handle 32 as they occur at the surgical instrument 30tip. Significantly, some of these forces may be so small that they needto be scaled up in level to be felt by the surgeon. Therefore, forcereflectance may enable the surgeon to actually feel feedback via thehandle which he is not naturally capable of feeling, thus enhancing hisor her sensing of instrument feedback during a procedure.

[0065] Contact sensing may also be enabled in the controller robot.Contact is a binary logic circuit in human neurology, i.e., either thereis contact with tissue or not. It is not a time varying function offorce as in force reflectance above. Therefore, the controller robot 10may harmonize the body's natural “binary” contact sensing circuit byimplementing a binary contact sensor and display (see FIG. 3, Contact“Yes,” “No”). Alternately, a scaled jerk motion may also be presented tothe handle 32 to represent contact. Such scaling may enable the surgeonto feel small contacts (i.e., delicate tissue) which would not benaturally felt.

[0066] Mini-endoscopic tip-vision capability is also taught andsuggested by the present invention to enable a view down the tip of theinstrument. Such a tip display or “instrument eye view” may enablevision from angles which are impossible to see through a traditionalmicroscope view finder. Displays for such endoscopes are shown as rightendoscopic tip display 60 and left endoscopic tip display 70 in FIG. 3.The displays may be capable of showing many views and magnifications,current position and history display of the course the instrument hastraveled during the operation. Playback of actual images, “instantre-play of the operation moves” may also be part of the historycapability.

[0067] It is also contemplated that the handle 32 may be interchangeableand exchangeable to mimic actual standard surgical handles depending onfield specific, surgeon specific, or operation specific conditions. Forexample, some handles may be squeezable, while some may be differentshapes. Such handles may be instrumented accordingly to receive relevantimpute from a surgeon.

[0068] In a second embodiment, the controller robot 10 of the presentinvention may take the form shown in FIG. 6. The components of thecontroller robot may include a robotics portion 602, a surgeonworkstation portion 604 (not illustrated in FIG. 6), a controllerportion 606, and a mobile base 608. The controller portion 606 may beintegrated with the robotics portion 602, the workstation portion 604,or the mobile portion 608. The robotics portion 602 may include left andright robotic arms 610, 612 (discussed further below) for carrying outcommanded actions. The robotics portion 602 may be adapted to be engagedto an adapter 614 attached to a surgical table 616 (not illustrated inFIG. 6), such that the positioning of the robotics portion 602 relativeto the surgical table 616 may be adapted for various types of procedureson varying portions of a patients anatomy simple by adjusting theposition of the adapter 614.

[0069] The ability to locate the robotics portion 602 at variouslocations relative to the surgical table 616 may allow different typesof surgery to be accomplished with the same controller robot 10.Furthermore, since an adapter 614 may be moved between surgical tables,use of a controller robot 10 may not be limited to a single operatingroom. Accordingly, the utility of the controller robot may be maximized,as the need to procure multiple controller robots for multiple operatingrooms can be avoided. Finally, an additional efficiency may be gainedthrough the reduction in cross training required by a surgeon where asingle piece of equipment is able to replace several different pieces.

[0070] The mobile base 608 may allow the components of the controllerrobot 10 to be portably located within the operating environment asdesired. As preparation of a patient may require the fullest accesspossible to the patient, it may be desirable to minimize the equipmentimmediately adjacent to the patient during a preparatory phase, whileretaining the ability to utilize robotics during the actual procedure.Accordingly, the ability to move at least the robotics portion 602 ofthe controller robot 10 into and out of the surgical field may providebenefits during the complete surgical procedure.

[0071] As shown in FIG. 6, the robotics portion 602 may be provided withfeatures for alternately engaging the robotics portion 602 to a mobilebase 608 or to table adapter 614. The engagement between the roboticsportion 602 and the mobile base 608 may be accomplished by a tongue ingroove joint 616, utilizing a rail feature 618 on the robotics portion602 and a channel 620 on the mobile base, to form a self aligning andsupporting engagement between the robotics portion 602 and the mobilebase 608 when the robotics portion 602 is engaged to the mobile base608. Additionally, retention features 622 such as a threaded retainingpin 624 may be provided to ensure retention of the robotics portion 602to the mobile base 608 when the robotics portion 602 is engaged to themobile base 608.

[0072] Similar engagement and retention features may be provided betweenthe robotics portion 602 and the table adapter 614. The use of the railin channel structure assists in orienting and positioning the roboticsportion relative to the table adapter 614, such that indexing theposition of the adapter 614 to the surgical table may allow correctindexing of the robotics portion 602 to the table 616. With regard tosome neurosurgical procedures (as well as other procedures), the patientmay be fixed relative to the table 616, such as through the use ofpositioning screws (such positioning screws are known and used in theneurosurgical art), such that the position of the patient may be indexedto the table 616. Thus, the position of the patient relative to therobotics portion 602 of the controller robot 10 may be established bythe indexing of the patient and the robotics portion 602 of thecontroller robot to the surgical table 616.

[0073] Dis-engagement of the workstation portion 604 shown in FIG. 7during procedure, through which a user controls the robotics portion602, from the robotics portion isolates any potential spurious motionsof the surgeon operator from the robotics portion 602, such that suchmotions are not inadvertently transferred to a patient through aninstrument or effector. Such isolation reduces the likelihood of harm asa result of any such spurious motion. Such isolation further may preventspurious motions of a patient from being transmitted to a surgeonoperator during a procedure, thus further reducing the likelihood ofharm resultant from spurious motions.

[0074] The mobile base 608 may be provided with features for allowingthe mobile base 608 to be alternately rolled around within a surgicalenvironment, or fixed relative to a specific position within theoperating environment. Such alternating function may be accomplished byproviding the mobile base 608 with both rollers 802 (shown in FIG. 8) orcasters, as well as jack screws 804 (shown in FIG. 8) to support themobile base 608 off of the rollers 802 or casters when it is desiredthat the mobile base 608 not move. Additionally, the robotics portiondock 626 on the mobile base 608 may be height adjustable relative to afloor on which the mobile base 608 is resting, such that the position ofthe robotics portion dock 626 may be adjusted relative to the roboticsportion 602 to allow alignment of the robotics portion 602 relative tothe dock 626 to allow engagement of the robotics portion 602 to the dock626.

[0075] The mobile base 608 may also be adapted to have the elementswhich comprise the surgical workstation portion engageable to the mobilebase 608. As shown in FIG. 7, the surgical workstation portion 604 mayinclude left and right controllers 702 704, as well as a user interface706 for displaying operation parameters and feedback signals to asurgeon using the controller robot 10. The user interface 706 may be atouch-sensitive display, allowing a user to select and set parameters,as well as to view graphic representations of feedback, such asdiscussed further below. The controller portion 606, which may includesoftware and hardware for converting inputs from the workstation portion604 into motions by the left and right arms 610, 612, may be integratedinto the workstation portion 604, such that the entire controller robot10, including the robotics, workstation and controller portions 602, 604and 606 may be transportable as a unit when engaged to the mobile base608. Alternately, the controller portion may be a preparation unit,attachable to the mobile base, or be remotely located away from theoperating environment.

[0076] The robotics portion 602 may include two arms 610, 612 havingseveral degrees of freedom to allow correct positioning and orientationof instruments and/or effectors attached to the ends of the arms. Thearms may include two sections, having at least two degrees of freedom ateach joint, or may have more than two sections allowing movements to beaccomplished by lesser motions at each joint.

[0077] The ends of the arms 610, 612 may be designed to allow differentinstruments or instrument magazines to be interchangeably attached tothe ends of the arms 610, 612. As shown in FIG. 9, the end 902 of an arm904 (a non-left/right specification is shown) may be formed by ainterchange block 906 having features for engaging a instrument unit,such as those discussed further below. The interchange block 906 mayalso be provided with instrument retention features, such as threadedrods 908 extending from a face 910 of the interchange block 906, whichare adapted to be received by a an instrument unit or instrumentmagazine (shown generically as 912 or FIG. 9). The threaded rods 908 maybe reversibly driven to allow the rods 908 to be alternately threadedinto or withdrawn from threaded receiver holes 914 on an instrument unit912. The interchange block 906 may also be provided with alignmentreceptacles 916 for receiving alignment pins 918 on the instrument unit912, to assure proper orientation and positioning of the instrument unit912 relative to the interchange block 906. A communications receptacle920 may also be provided on the face of the interchange block 906, forreceiving a communications connector 922 on an instrument unit 912 toallow communication of electrical signals between the interchange block906 and the instrument unit 912.

[0078] The interchange block 906 may have two degrees of freedomrelative to the wrist 924 of the arm. These degrees of freedom may be arotational degree of freedom 930 about a finger pin axis 926 extendingthrough a finger pin 928, and a rotational degree of freedom 932 aboutan axis 934 perpendicular to the axis 926 through the interchange block906 and an engaged instrument unit. The degree of freedom 930 about thefinger pin axis 926 may be provided by mounting the interchange block906 to a wrist block 936 through the finger pin 928. The finger pin maybe provided with a non-circular cross section, such that the interchangeblock 906 can not rotate about the pin 928. The pin 928 may extend froma wrist motor 938 mounted to the wrist block 936, such that rotation ofthe pin 928 caused by the wrist motor 938 will cause the interchangeblock 906 to rotate about that axis 926. The interchange block 906 maybe retained to the finger pin 928 by a fastener 939 threaded into theend of the finger pin 928 to retain the interchange block 906 to thefinger pin 928. Slip rings 940 may be provided between the interchangeblock 906 and the wrist block 936 to allow communication of electricalsignals between the interchange block 906 and the wrist block 936 duringrotation of the finger pin 928. Alternately, a flexible wire bundle (notshown) may be provided between the wrist block 936 and the interchangeblock 906, although the use of a flexible cable bundle may requireimposition of a limit on the range of rotation through which theinterchange block 906 may be rotated.

[0079] The interchange block 906 may be provided with an annular channel942 surrounding the outer surface 944 of the interchange block 906, toallow a sterile sheath 944 to be retained to the interchange block 906.As shown in FIG. 10, the sterile sheath may extend from the interchangeblock 906 down the arm to which the interchange block 906 is connected,and may further extend to encompass all or substantially all of therobotics portion 602 to provide a sterile barrier between the roboticsportion 602 and a patient on whom the controller robot 10 is being used.

[0080] The use of the interchange block 906 allows varied instruments tobe implemented on the end of the arm 610, 612, such that the samerobotics portion 602 may be used for different surgical proceduressimply by changing the available instruments for the arm. Furthermore,the instruments available for use during a procedure may be expandedthrough provision of instrument units which carry multiple instruments(hereafter referred to as instrument magazines), through the use ofinstrument trays attached to the robotics portion 602 (such as thoseshown in FIG. 6 as reference 628), or through the use of instrumenttrays containing instrument magazines. The incorporation of featureswhich allow an arm 610, 612 to connect to or disconnect from instrumentunits allows such instrument units to swapped onto the end of the arm610, 612 with minimal manual intervention from a surgeon operator.

[0081] The capability of using multiple instrument units on the arms610, 612 of the robotics portion 602 requires the adoption of a standardinterface between the instrument unit and the interchange block 602. Thestandard interface should include both the mechanical interfacedefinition, as well as the electrical interface definition. Theelectrical interface definition should be able to provide availablecommunications paths for each type of signal which may be needed to becommunicated between a an instrument unit and the controller portion606.

[0082] An illustrative probe instrument unit is shown in FIG. 11 Theprobe 1102 shown may be used to press on or move tissue during aprocedure. As shown, the probe 1102 may be connected to its instrumentunit 1104 through a load cell 1106, which may be capable of measuringforces in one or more directions. The use of the load cell 1106 allowscommunication of the amount of force that the probe 1102 is applying tobe communicated to the controller portion 606, which may then use theinformation for other purposes, such as for generation of feedback to asurgeon operating the controller robot. The load cell 1106 will likelyrequire the presence of an excitation voltage, as well as availablepaths for communicating response values from the load cell 1106. Thesesignals may be communicated to the controller portion 606 in eitheranalog or digital form. If the signals are communicated in an analogform, the analog signal would need to be converted to a digital signalin the controller portion 606. Such analog to digital capturecapabilities are available in programmable form, such that the sameanalog to digital unit or units in the controller portion would be ableto receive and transform signals from varying types of sensors providedin a instrument unit.

[0083] The instrument unit may additionally be provided with featuresfor assisting a surgeon operator in determining the distance of aninstrument from a piece of tissue. Although the use of binocular viewingdevices can provide depth information, the use of monocular viewers, ortwo dimensional displays, reduces the availability of visual depthperception cues. Accordingly, it may be desirable to provide cueing forthe surgeon operator to assist the surgeon operator in determiningdistance from and predicting contact with tissue.

[0084] One potential visual aid is the addition of a visible lightpointer 1108 to indicate the direction in which the probe 1102 ispointing. The power of the light source 1110 must be maintained at aminimum to limit any adverse tissue heating affects. Accordingly, thesize of the light source 1110 may be maintained small enough such thatthe source 1110 may be built into the instrument unit 912, slightly offaxis from the probe 1102 itself. The inability to have the light 1112point directly down the axis 1114 of the instrument may be offset byaiming the light 1116 at a point of contact 1118 immediately in front ofthe position where the probe 1102 would contact tissue 1120, such thatthat the surgeon would be able to estimate distance to instrumentcontact based on the gap between the probe 1102 and the projected pointof light, relative to the size of the probe 1102 and the viewed motionof the probe 1102.

[0085] A variation on the single light distance cueing is the use of aproximity sensor. A proximity sensor may use a transmitter and receiverpair to determine the distance between the transmitter and a surface.The measured distance may be compared to the known length of a probe todetermine the distance between the end of the probe and tissue in frontof the probe. As shown in FIG. 12, the transmitter 1202 and receiver1204 may be off-set on opposite sides of the probe 1102, such that thedistance being measured is the distance between the end of the probe andthe tissue, rather than the tissue off-set a distance from the probe1102.

[0086] The distance between the end of the probe 1102 and the tissue maybe represented to the surgeon through a visual or audible displaypresented on the workstation portion 604. For example, an auralindicator, declining in magnitude until zero at contact, may beprovided. Alternately, a graphical read out of the distance between thetissue and the end of the instrument may be presented, or the distancemay be presented in a graphical format, such as a vertical bar graphindicating the distance between the end of the instrument and thetissue.

[0087] As shown in FIGS. 13 and 14, an alternate distance cueingcapability may be created by providing two light pointers 1302, 1304,such that when aligned, the points are projected onto the tissue pastthe instrument. Due to the angle between the light paths, the distanceΔ, shown in FIG. 14, between the projected points will increase when theinstrument is farther away from the tissue, and decrease as theinstrument comes closer to the tissue, until the projected points oflight are projected onto the same point immediately before contact.

[0088] The instrument units themselves may be provided with thenecessary structure for interfacing with the interchange block directly,such as shown in FIG. 15. The instrument unit 912 shown in FIG. 15 isalso provided with a video camera 1502 to allow a instrument's eye viewto be obtained for the surgeon, such that the view may be provided to asurgeon operator through instrument view displays (such as those shownin FIG. 16).

[0089] Instrument units 912 may alternately be designed to allow severalinstrument units to be contained in a magazine which can be engaged tothe interchange block. In such a configuration, some form of ability toextend and retract the individual instrument units must be provided, toallow the motion of the instrument in the operation site withoutincreasing the risk of accidental contact between not-in-use instrumentsand patient tissue.

[0090] A notional instrument magazine is shown in FIG. 17 showing twoinstrument units 1702, 1704 in a magazine 1706, with a probe instrumentunit 1702 shown in an extended position and a forceps instrument unit1704 shown in a retracted position. A latch 1708 may be provided topositively engage an extended instrument unit with a drive 1710 forextending the instrument unit. Additionally, contacts 1712 forelectrical communication between the instrument unit 1702 and themagazine 1706 may be provided on the outer surface of the instrumentunit 1702, such that different instrument units may be engaged in themagazine 1706. Where a magazine 1706 is utilized, a instrument's eyeview camera 1714 may be incorporated into the magazine 1706, allowingthe complexity of instrument units to be kept at a minimum. The magazine1706 may be provided with features for engaging the interchange block,including alignment pins 1716, and an electrical connector 1718 forproviding a communications path between the instrument units and aremotely located controller portion 606.

[0091] The notional magazine shown may use a rotary pattern, in whichinstrument units are rotated about the long axis of the magazine 1706until located in a deployment station. In the deployment station, anextension drive 1720 may move the instrument unit forward to a deployedposition, in which a surgeon can direct the effector portion of theinstrument as required for an on-going procedure.

[0092] The use of instrument magazines allows quicker instrument accessover requiring a robotic arm to move to a instrument change station,thus providing a more efficient surgical procedure. The selection ofinstruments to incorporate in a magazine, however, is a trade-offbetween the allowable size of the magazine, especially in the surgicalsite, versus the speed with which instruments must be accessible. Theuse of instrument trays to hold spare magazines with differentinstrument mixes allows utilization of a magazine tailored for aspecific portion of a procedure, while retaining a larger selection suchas can be made available on a instrument tray. Thus, the instrumentsprovided in a magazine can be instruments which will be needed rapidlyor frequently, while instruments kept in magazines on the instrumenttray may be instruments needed at a later point in the procedure, orinstruments for which the change-overtime required to change a magazineis not as critical. Furthermore, the instrument tray may be used to holdboth instrument magazines and instrument units adapted to engage theinterchange block.

[0093] Furthermore, the instrument trays may be replaced during aprocedure, such that several different mixes of magazines and individualinstrument units may be utilized during a procedure. The mixes selectedmay be dependant on the surgeon utilizing the controller robot, as wellas on the procedure being performed. Individual instrument trays may bemarked to allow the controller robot 10 to identify instrument magazinesand instrument units loaded into a tray, such that the controllerportion 606 may display correct selection parameters to a surgeon duringa procedure, as well as provide feedback when a instrument is notavailable in a given mix of instrument units in magazines and individualinstrument units. The marking may be accomplished by providing anidentifier for a tray, and having a stores list for the tray pre-storedin the controller portion, or may utilize auto-detection capabilities toquery instrument units in the tray to identify themselves.

[0094] As shown in FIG. 7 the workstation comprises the interfacebetween the surgeon and the controller portion 606, and accordinglyshould be configured to provide necessary information to a surgeonduring a procedure, as well as to receive necessary input from thesurgeon during the procedure. Typically, surgeons use vocal commands toreceive assistance from other personnel in the operating theater inorder to minimize the actions required from the surgeon apart from theprocedure itself. For example, a surgeon desiring a different instrumentthan the one presently in hand may verbally request to be provided witha different instrument. Thus, the workstation may preferably includespeech recognition capabilities to allow the surgeon to function in amanner consistent with traditional practices.

[0095] The workstation may include three types of input capabilities:instrument position, speech recognition, and manual selection. Theinstrument position input may be received via left and right instrumentinput devices 702, 704, as described above. The instrument input devicesmay comprise articulated arms which allow a surgeon to operate handles710, 712 in a manner consistent with the motions that would be requiredto manually utilize the instrument in question. As shown in FIG. 18, thehandles 710, 712 may be connected to the arms 702, 704 through a loadsensing device 1802, able to determine the forces which are beingapplied to a handle 710. The load sensing device may be a six-axis loadcell, able to measure forces in three axes and torques in three axes.

[0096] Gross motion of the handle may be allowed through the use of anintermediate arm section 1804 or sections. The intermediate arm section1804 or sections may utilize one or more degree of freedom motion ateach end of the section, similar to the joints of the robotics portionarms, to allow motion to be imparted through the controller. Feedbackmay be provided to the surgeon through coupling of feedback mechanisms1808 in each degree of freedom. The handle 710 may be provided with arotational degree of freedom about the long axis of the handle 1806. Afeedback mechanism, such as a stepper motor controlled by the controllerportion of the controller robot (not shown), may be used to both provideresistance to rotation of the handle by the surgeon, as well as vary theresistance and reflective force based on feedback being measured at aninstrument.

[0097] The intermediate arm 1808 or arms may be connected to a base arm1802 through a joint having one or more degrees of freedom, with eachdegree of freedom being coupled with a feedback mechanism. Finally, thebase arm 1802 may be connected to the workstation structure (not visiblein view) through a joint 1812 having one or more degrees of freedom,with each degree of freedom being coupled with a feedback mechanism.Furthermore, each joint should be provided with position sensing means,such a variable resistance potentiometer, to allow the controllerportion to determine the position and orientation of the handle while inuse.

[0098] The mechanism may be designed so as to allow smooth motion in thesix degrees of freedom 1814 of a simple handle. The six degrees offreedom may correspond to deflections in three axes, as well as rotationin three axes.

[0099] The handle itself may include an additional degree of freedom1816, such that seven degrees of freedom define motions of the handle.The seventh degree of freedom may be associated with the clamping of thegrip, such as where two grips 1818, 1820 are levered to allow anoperator to emulate the motion of scissors, forceps, or a hemostat.Since different instruments may require different motions at the handle,the handle may be rapidly interchangeable through the use of a connector1822 between the handle 710 and the intermediate arm 1808.

[0100] Returning to FIG. 7, the workstation structure may additionallybe provided with adjustable supports 714, 716 to provide stability to asurgeons arms during a procedure. The ability to adjust the position ofthe supports 714, 716 allows the surgeon to correctly position his orher arms relative to the handles 710, 712 during a procedure.

[0101] Verbal input may be received into the workstation through theincorporation of a microphone 718. The microphone 718 may be external tothe structure of the workstation, such as in the form of a clip onmicrophone or boom microphone extending from the workstation, or may bebuilt internally in the workstation. Such a design choice is dependanton the ability of the microphone 718 selected to adequately detectcommends uttered by the surgeon during a procedure, while remaining in anon-interfering location.

[0102] Manual entry capabilities may also be provided, such as throughthe use of a touch screen display 708. Alternately, other pointingdevices (not shown), such as a mouse, trackball, or force post may beutilized, however it may be beneficial to minimize the necessity for asurgeon to remove his or her hands from the handles during a procedure.Finally, display commands may be received from a surgeon via themicrophone in response to verbal commands. Alternately, an auxiliarydisplay and input device may be provided to allow an assistant to thesurgeon to be responsible for manual data entry during a procedure.

[0103] Instrument eye view displays may either be provided adjacent tothe left and right robotic arms, where the surgeon is locatedimmediately adjacent to the surgical field, or through instrument eyeview displays 1604, 1606 incorporated into a display presentation on theworkstation (such as is shown in FIG. 16). The use of a graphical userinterface allows displays to be generated by the controller portionbased on the needs of the surgeon at that point in a procedure, or inresponse to pre-programmed or manually selected parameters provide bythe surgeon.

[0104] In addition to force and motion feedback provided to the surgeonthrough the handles, visual feedback can be provided through the displayon the workstation. A notional display is shown in FIG. 16 showing anillustrative force/response curve resultant 1602 from pressing a probeas discussed above against tissue, showing both a force deflection curve1608 resultant from imposing the probe against the tissue, as well as ahysteresis curve 1610 resultant from a controlled withdrawal of theprobe from the contact with the tissue. Selection of sensor displays maybe voice activated, such that a surgeon can reconfigure the display asrequired during a procedure. Alternately, the reconfiguring of thedisplay can be the responsibility of an assistant in verbalcommunication with the surgeon during the procedure, such as through anauxiliary interface (shown in FIG. 8).

[0105] The controller portion 606 of the controller robot 10 may be ableto cross control instruments when selected. Thus, the operator couldelect to control a instrument on a left robotic arm through a righthandle on the workstation. The controller logic may provide additionalfunctionality during such cross-control utilization, such as locking outthe non-used control to limit the likelihood of control confusionresulting from simultaneously cross controlling multiple instruments.Additionally, display parameters may be imposed during suchcross-controlled utilization, such as enforcing the selectedinstrument's instrument-eye view for the primary display duringcross-controlled utilization.

[0106] The controller portion 606 of the controller robot 10 may includea general purpose computer operating a program for controlling motion ofthe robotic arms as a result of input from a surgeon via theworkstation. Accordingly, the controller software may be designed toenable to controller to assist the surgeon in varying ways, such as theimposed limitations associated with cross-controlling discussed above,or the generation of the force/response and hysteresis display shown inFIG. 16

[0107] The information obtained from a sensor such as the probeillustrated in FIG. 12 may be used for more than simple feedback to thesurgeon. Analytical methods may be applied to the results to providecharacterizations to a surgeon. For example, tissue stiffness orhysteresis values obtained from force/position information obtained froma probe may be compared to cataloged tissue characteristic inform suchas information stored in a remote database 806 as shown in FIG. 8. Thecharacteristics of the tissue may be matched with known tissue values,or may be compared with known values for particular tissue type selectedby the surgeon. Other sensors may be selected as useful during theprocedure (while such sensors are incorporated into a instrument unit ormagazine) to allow a surgeon to obtain a variety of parameters(temperature, mechanical characteristics of tissue, oxygen saturation ofblood adjacent to a surgical site, etc.), or to allow the surgeon toselect control points in a surgical field. Such control points may beutilized to identify boundaries for allowable motion of the instrumentsor other elements of the robotics portion of the controller robot.Furthermore, connections to external systems such as continuousframeless navigation capabilities may allow the externally obtained datato be superimposed into displays presented on the workstation, such as amicroscope view

[0108] The principal purpose of the controller portion, 606 however, isto translate the inputs of the surgeon as provided through the handlesinto motions made by instruments engaged to the arms of the roboticsportion. Parameters may be provided by the surgeon to affect the motionof the robotic arms and instruments in response to input commandsprovided by a surgeon through the handles. As discussed above, scalingof motions and forces may assist a surgeon in working in miniature, asmay be required during some procedures. Additionally, damping parametersmay be applied to provide increased controllability of instrumentsduring a procedure.

[0109] The use of parameters may be implemented to provide a robustsituation for motion of the instruments, such that maximum speedconstraints, maximum motion constraints, motion damping, and controlledarea prohibitions may be implemented as requested by a surgeon to assistthe surgeon during a procedure. Controlled area prohibitions may beimplemented based on control points identified by the surgeon, such thatthe controller portion may maintain a spatial model of the geometry ofthe patient and surrounding structures to prevent contact betweeninstruments or any other portion of the robotics portion and prescribedareas. Offsets may be provided based on control points, such that theactual geometry of a prescribed area may be determined based on locatedreference points without requiring contact with the actual prescribedarea, or to impose a no-contact safety margin between a prescribed areaand an instrument or other part of the robotics portion.

[0110] The inviolability of the prescribed area may further be enhancedthrough the implementation of predictive motion modeling to generateexpected position information, such that interference determinationsbetween a prescribed area and an instrument position may be based notonly on the position of the instrument, but also on the existing path ofthe instrument in motion, such that potential or predicted contact witha prescribed region may be signaled to the surgeon prior to such contactoccurring, as well as allowing smoothing of the motion of the instrumentadjacent to such a prescribed area. For example, as the contactpotential measured as a factor of distance, direction of travel, andinstrument speed, increases, the controller portion 606 mayautomatically increase motion damping and decrease maximum instrumentvelocity allowable, to provide the surgeon with greater control adjacentto the prescribed portion.

[0111] The ability to impose motion constraints, such as maximuminstrument velocity, maximum instrument acceleration, and maximuminstrument force, may be implemented to limit the likelihood of unwantedcontact or spurious motions by the instrument. Force limitations may beapplied to prevent damage to tissue which could result fromover-application of force to tissue. Accordingly, it may be beneficialto provide for rapid configuration of the instrument force limit, toallow a surgeon to vary the instrument force limit based on an expectedtissue type. Such a determination may further be assisted through theuse of a catalog of force limitations based on tissue type, such thattissue type determinations obtained through external analysis, such asmagnetic resonance imaging or computer aided tomography, may be appliedto the spatial model of the surgical field to vary force limits based ontissue types defined by the external analysis.

[0112] The controller portion may be provided with a means forcommunicating information obtained during a procedure with externalprocessors, to allow integration of the information utilized by thecontroller portion with information in use by other equipment in thesurgical theater or hospital environment in general. For example, anetwork connection may be utilized by the controller portion to receivedata obtained by magnetic resonance imaging or computer aided tomographyto provide information for a spatial model of the surgical field.Alternately, the positions of each portion of the robotic arms may beused to determine the position of an instrument, such that theinformation could be exported to continuous frameless navigationequipment to allow the position of the instrument within the surgicalfield to be communicated to and integrated with the spatial informationcontained within the continuous frameless navigation equipment, orwithin the imagery presented by a enhanced viewing equipment, such as aelectronic microscope. Other information, such as control points, couldalso be communicated between the pieces of equipment, such that theinformation could be overlayed into the other pieces of equipment. Forexample, a pre-defined prescribed area could be shaded in an electronicpresentation of a microscope or instrument eye view, to inform thesurgeon of the presence of and location of the prescribed area during aprocedure, without requiring the surgeon to change attention from onedisplay to another.

[0113] The exporting of information from the controller portion toexternal equipment may also allow remote storage of historical procedureinformation, such as the instrument selection and instrument position atany point during a procedure, such that the stored information could belater used to replay a procedure for teaching or review purposes.Furthermore, since the connection between the surgeon and the roboticsportion is electrical, the stored information could be utilized togenerate a replay of the handle positions and feedbacks, to allow aphysician to follow through the procedures without actually creatingmotion of a robotics portion, while viewing the displays presented tothe surgeon during the procedure.

[0114] Stored data may also be utilized to generate predictive selectionof instruments for a surgeon prior to and during a procedure. Forexample, a certain surgeon may utilize a specific group of instrumentsfor a specific type of procedure, distinguishable from the instrumentsthat a different surgeon would select. Archived instrument selectioninformation would allow provisioning of instrument trays based on thesurgeons prior instrument selections, reducing the effort required todetermine instrument provisioning for a procedure. Alternately, expectedinstrument information could be presented to an assistant to thephysician to allow the assistant to review and confirm instrumentselection based on the expected instrument selections, such as throughthe auxiliary workstation, further improving the efficiency ofinstrument provisioning in the surgical theater.

[0115] Finally, archived instrument selection information could be usedadministratively, such as to generate billings for instruments usedduring a procedure. Such use would reduce the administrative overheadassociated with determining instrument usage for billing after aprocedure.

[0116] Other variations and modifications of the present invention willbe apparent to those of skill in the art, and it is the intent of theappended claims that such variations and modifications be covered. Theparticular values and configurations discussed above can be varied andare cited merely to illustrate a particular embodiment of the presentinvention and are not intended to limit the scope of the invention. Itis contemplated that the use of the present invention can involvecomponents having different characteristics as long as the principles ofthe invention are followed.

What is claimed is:
 1. A method of controlling a robotically drivensurgical instrument for a surgeon comprising the steps of: locating acontroller robot between a handle and the surgical instrument; sensingincident tremor force components applied by a surgeon to the handle;modulating the incident tremor force components to generate modulatedtremor force commands; and applying through the controller robot themodulated tremor force command onto the surgical instrument.
 2. Themethod of claim 1 further comprising the step of displaying a signalrepresenting the modulated tremor force on a display.
 3. The method ofclaim 1 further comprising the step of controlling and adjusting themodulated tremor force via a modulation parameter provided by a surgeon.4. The method of claim 3 wherein the modulation parameter is dependantupon historical data associated with a surgeon.
 5. The method of claim 3wherein the modulation parameter is dependant upon input provided by asurgeon during a procedure.
 6. The method of claim 1 wherein at the stepof applying the modulated tremor force commands, the modulated tremorforce commands are applied in all degrees of freedom of the surgicalinstrument.
 7. The method of claim 1 wherein at the step of modulatingthe incident tremor force compounds, the moduated tremor force commandsare scaled dependent on a scaling paramenter.
 8. The method of claim 1wherein at the step of outputting through the controller robot amodulated tremor force on the surgical instrument the output is smoothed9. The method of claim 1 wherein at the step of modulating the incidentforce, force components, the modulated tremor force commands, orsmoothed to eliminate anomolies.
 10. A method of controlling a surgicalinstrument connected to a surgical robot comprising the steps of:locating a controller robot between a handle and a surgical instrument;sensing incident reflectance force from a sensor when the surgicalinstrument is placed against body tissue; modulating the reflectanceforce components in the controller robot; and outputting through thecontroller robot a modulated reflectance force on the handle, whereinthe modulation scaling step includes modulating the reflectance force inall degrees of freedom of the handle.
 11. The method of claim 10 whereinthe output is outputted in all degrees of freedom of the handle.
 12. Amethod of controlling a surgical instrument comprising the steps of:locating a controller robot between a handle and a surgical instrument;sensing incident force components present on the handle generated by asurgeon's hand; modulating the incident force components in thecontroller robot; and outputting through the controller robot amodulated force on the surgical instrument, wherein the output stepincludes the further step of outputting the modulated force in alldegrees of freedom of the surgical instrument.
 13. The method of claim12 comprising the further step of scaling the modulated force to ascaled output level for outputting through the controller robot.
 14. Asurgical robot comprising: a controller robot located between a handleand a surgical instrument; a sensor for sensing an incident reflectanceforce from the sensor when the surgical instrument is contact with bodytissue; a modulator for modulating the reflectance force components inthe controller robot; and a motor for outputting through the controllerrobot a modulated reflectance force on the handle.
 15. A method ofcontrolling a surgical instrument connected to a surgical robot for asurgeon comprising the steps of: receiving from a surgeon operator inputfrom an input device indicating desired forces and deflections of arobotically controlled surgical instrument; transforming the input intocontrol signals for directing the motion of and application of force bya robotically controlled surgical instrument; applying the controlsignals to a robotically controlled surgical instrument; monitoringforces applied to the robotically controlled surgical instrument by apatient's tissue in response to motion of the robotically controlledsurgical instrument; and applying resistive forces correlating to themonitored forces to the surgeon operator's input device in response toinput provided by a surgeon operator; wherein said resistive forces varysufficiently rapidly to emulate forces resultant from tremor motions ofa surgical instrument against a patient's tissue.
 16. A method ofcontrolling a surgical instrument according to claim 15, furthercomprising the step of scaling the operator input to reduce themagnitude of forces and deflections applied by the roboticallycontrolled surgical instrument.
 17. A method of controlling a surgicalinstrument according to claim 16, further comprising the step of scalingresistive forces applied to the input device to increase indicatedforces to a level detectable by a surgeon operator.
 18. A controllerrobot for performing surgical procedures, the controller robotcomprising: a robotics portion, the robotics portion comprising at leastone surgical instrument unit; an workstation portion, said workstationportion comprising a display and an input device; a controller portion,the controller portion comprising hardware and software for transforminginput provided by a surgeon operator via the interface portion intomotion of the at least one surgical instrument; wherein the roboticsportion further comprises force detection sensors for determining forcereflectance from tissue in contact with the at least one surgicalinstrument.
 19. A controller robot according to claim 18, wherein saidrobotics portion comprises a left robotic arm and a right robotic arm,and wherein the interface portion comprises a left input device and aright input device.
 20. A controller robot according to claim 19,wherein the right input device is able to control motion of the leftrobotic arm.
 21. A controller robot according to claim 18, wherein theinput device is engageable to a handle emulating the handle of asurgical instrument, and further is capable of receiving input from thehandle in six degrees of freedom.
 22. A controller robot according toclaim 21, wherein said input device is further capable of receivinginput from a seventh degree of freedom, said seventh degree of freedomassociated with the opening or closing of a levered handle.
 23. Acontroller robot according to claim 21, wherein said input device isfurther adapted for alternately receiving varying handles emulatinghandles of surgical instruments in use.
 24. A controller robot accordingto claim 18, wherein the robotics portion further comprises at least onerobotics arm, the robotics arm adapted to alternately engage varyingsurgical instrument units.
 25. A controller robot according to claim 24,where said robotics portion further comprises a supply of varyingsurgical instrument units, the surgical instrument units adapted toalternately engage the robotics arm.
 26. A controller robot according toclaim 25, wherein the controller portion further comprises capability todirect the robotics arm to select specific surgical instrument units forengagement to the robotics arm.
 27. A controller robot according toclaim 26, wherein said interface portion further comprises a microphonefor receiving spoken input from a surgeon operator, and wherein saidcontroller portion selects a surgical instrument unit for engagement tothe robotics arm dependant on input received via the microphone.
 28. Acontroller robot according to claim 18, wherein the robotics portionfurther comprises a left robotics arm and a right robotics arm, therobotics arms adapted to alternately engage varying surgical instrumentunits.
 29. A controller robot according to claim 28, where said roboticsportion further comprises a left supply of varying surgical instrumentunits and a right supply of varying surgical instrument units, thesurgical instrument units adapted to alternately engage the roboticsarms.
 30. A controller robot according to claim 29, wherein thecontroller portion further comprises capability to direct the roboticsarms to select specific surgical instrument units for engagement to therobotics arms.
 31. A controller robot according to claim 30, wherein thevarying surgical instrument units are selected dependant on a procedureto be performed.
 32. A controller robot according to claim 31, whereinthe varying surgical instrument units making up the left supply are notidentical to the varying surgical instrument units making up the rightsupply.
 33. A controller robot according to claim 32, wherein the leftsupply further comprises at least one instrument magazine engageable tothe robotics arm.
 34. A controller robot according to claim 32, whereinthe right supply further comprises at least one instrument magazineengageable to the robotics arm.
 35. A controller robot according toclaim 18, further comprising a table adapter, the table adapter forreceiving the robotics portion and indexing the robotics portion to aknown location on the table.
 36. A controller robot according to claim35, wherein the robotics portion is selectively detachable from themobile base when the robotics portion is engaged to the table adapter.37. A controller robot according to claim 18, wherein the workstationportion is engageable to the mobile base.
 38. A controller robotaccording to claim 18, wherein the controller portion is engageable tothe mobile base.
 39. A controller robot according to claim 18, furthercomprising an auxiliary interface connected to the controller portion.40. A controller robot according to claim 39, wherein the controllerportions connected to a communications network.
 41. A controller robotaccording to claim 40, further comprising a database connected to saidnetwork, said database storing parameters associated with surgeons. 42.A controller robot according to claim 40, further comprising a databaseconnected to said network, said database storing parameters associatedwith tissues.
 43. A controller robot according to claim 40, furthercomprising a database connected to said network, said database storinghistorical information associated with performance of a medicalprocedure using the controller robot.
 44. A controller robot accordingto claim 40, further comprising continuous frameless navigationequipment connected to said network.
 45. A controller robot according toclaim 40, further comprising computer aided tomography equipmentconnected to said network.
 46. A controller robot according to claim 40,further comprising magnetic resonance imaging equipment connected tosaid network.
 47. A controller robot according to claim 18, wherein saidat least one surgical instrument unit further comprises an imager, saidimager viewing an area associated with a surgical instrument.
 48. Acontroller robot according to claim 18, wherein said at least onesurgical instrument comprises distance cueing capabilities.
 49. Acontroller robot according to claim 48, wherein said distance cueingcapability comprises distance measuring equipment.
 50. A controllerrobot according to claim 48, wherein said distance cueing capabilitycomprises a plurality of light beams, the light beams aimed to convergeat a location immediately in front of a surgical instrument associatedwith the surgical instrument unit.
 51. A controller robot according toclaim 18, wherein said workstation portion signals instrument contactwith tissue to a surgeon operator when forces are first detected againstthe at least one instrument unit by the force detection sensors.
 52. Acontroller robot according to claim 18, wherein the controller portionis able to modulate control signals to the robotics arm dependant on ainstrument lag parameter.
 53. A controller robot according to claim 18,wherein the controller portion is able to modulate control signals tothe robotics arm dependant on a instrument motion damping parameter. 54.A controller robot according to claim 18, wherein the controller portionis able to modulate control signals to the robotics arm dependant on ainstrument speed parameter.
 55. A controller robot according to claim18, wherein the controller portion is able to modulate control signalsto the robotics arm dependant on an instrument force parameter.
 56. Acontroller robot according to claim 18, wherein the controller portionis able to receive definition of a boundary past which a surgicalinstrument should not travel, said controller further being able tolimit motion of the robotics arm to prevent interference between thesurgical instrument and the boundary.
 57. A controller robot accordingto claim 56, wherein the controller portion predicts a future positionof a surgical instrument dependant on the present motion of the roboticsarm, and further signals a surgeon operator when such predictionindicates a likely interference between the surgical instrument and theboundary.